Three negative point charges lie along a line as shown in the figure.

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Three negative point charges lie along a line as shown in the figure. Find the magnitude and direction of the electric field this combination of charges produces at point P, which lies 6.00 cm from the -2.00 microC charge measured perpendicular to the line connecting the three charges.

I've used the Pythagorean theorem to find the d for the outside two electric fields, E1 and E2. And I know the y components cancel out because the charges are negative and counteract. I've also converted the cm to m and the microCoulombs to Coulombs.

Adding up the Y vectors, I got 5.40 x 10^6; but this answer is wrong. I've been told that it needs to be some number x 10^7, but I have no idea what I'm doing wrong. Could someone please show me with steps what I'm doing wrong? It would really be helpful!

I went back through my stuff with a proverbial fine-toothed comb and found the error. I had my E1 charge as 2 x 10^-9 instead of 2 x 10^-6. When I re-added everything up, it came out to 1.398 x 10^7. Somehow this answer is still wrong. Any help?